This invention relates to optical fiber trays used in fiber distribution flames.
Optical fiber distribution frames are important components in telecommunications systems as an interface between optical fiber feeder (trunk) and distribution (transmission) cables. Typically, the feeder cables are fed into each tray of the frame from the back or side of the tray in the form of bundled fibers covered by protective tubing. The individual fibers are spliced to fiber pigtails on a splice tray, and optical connectors on the opposite ends of the pigtails are mounted in a panel near the front of the tray (see, e.g., U.S. Pat. No. 5,071,211 issued to Debortoli et al. and U.S. Pat. No. 4,898,448 issued to Cooper). Jumper cables are optically connected to the pigtail fibers by means of the connectors at the front of the trays for optical connection to other equipment.
In such frames, it is desirable to provide as high a density of fibers and connectors as possible while still permitting easy access to the connectors and splice trays for proper maintenance. For access purposes the fiber trays are usually slidable within a shelf, and can include a drop-down portion for access to the connectors (see, e.g., U.S. Pat. No. 5,129,030 issued to Petrunia and U.S. Pat. No. 5,071,211 issued to Debortoli et al.).
The use of movable trays can create problems as to how or where excess fiber can be stored within the apparatus, especially in high density applications. A further concern is how to protect the connectors and splices in a manner consistent with easy access.
In lightguide cross-connection applications typically used in central offices, the feeder cables are fed into the trays from the back. However, for interconnection applications such as typically used for cable television, the feeder cables are usually provided in the front of the trays. It is desirable, therefore, to provide a tray which can receive a cable from the front or back of the frame.